Classic history and presentation: This condition may present with pain located in the shoulder, but often pain localizes to the lateral aspect of the arm in the deltoid region. Tears due to traumatic injury (including a fall or shoulder dislocation) usually present with acute pain and limited motion, but chronic tears may have a more indolent course and a gradual onset of symptoms. Depending on the degree of the tear, patients may also show signs of weakness and limited active shoulder range of motion (ROM). Patients will often report difficulty in performing overhead tasks or repetitive tasks and lifting with the arms away from the body (reaching type activities).

Prevalence: Rotator cuff tears are very common in the elderly population.

• Age – The condition is uncommon in patients younger than 40 years (less than 4% incidence), but it is estimated to affect between 20% and 30% of individuals older than 60 years. As many as 50% of patients older than 80 years have full-thickness rotator cuff tears. While young patients are much less likely to experience rotator cuff tears, those who do are usually involved in throwing / overhead sports or experience a major traumatic event affecting their shoulder (such as a dislocation, falling off a horse, motor vehicle accident, or power lifting injury).
• Sex / gender – Men are more commonly affected than women.

Risk factors: Risk factors for rotator cuff tears, other than age, include smoking, hypercholesterolemia, and a family history of similar conditions. Additionally, look for a history of falls or shoulder dislocation in patients older than 40 years. Consider the possibility of Parkinson disease when evaluating an older individual, because rotator cuff injury is often seen in patients with Parkinson. Additionally, patients who use a wheelchair and depend upon their upper extremities to help transfer themselves are at increased risk for developing rotator cuff tears.

Pathophysiology: While acute tears are usually the result of traumatic injury, the pathophysiology of chronic or acute-on-chronic tears is thought to involve intrinsic degeneration of the supraspinatus, infraspinatus, teres minor, or subscapularis (SITS) muscles over time, due to a combination of impingement and imbalanced loading. There is likely a genetic component that has not been elicited that also contributes to rotator cuff tearing.

Grade / classification system: Goutallier Classification – described on CT or MRI is a way to evaluate the extent of fibrofatty infiltration of a torn rotator cuff muscle-tendon unit.

Stage 0: Normal muscle, no fat
Stage 1: Few fatty streaks in muscle
Stage 2: Less fat than muscle within the muscle
Stage 3: Same amount of fat and muscle within the muscle
Stage 4: More fat than muscle within the muscle